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- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR%3A_Experimental/Pulse_SequencesA pulse sequence is a succinct visual representation of the pulses and delays used in a certain NMR experiment. Depending on the experiment there may be hundreds of pulses! This page is dedicated to u...A pulse sequence is a succinct visual representation of the pulses and delays used in a certain NMR experiment. Depending on the experiment there may be hundreds of pulses! This page is dedicated to understanding what a pulse sequence is and how to understand the pictorial representations, as well as terms commonly used to describe parts of pulse sequences.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_TheoryNuclear magnetic resonance has been play an important role in the fields of physical techniques available to the chemist for more than 25 years. It is becoming a more and more useful method to probe t...Nuclear magnetic resonance has been play an important role in the fields of physical techniques available to the chemist for more than 25 years. It is becoming a more and more useful method to probe the structure of molecules. The primary object of this module is to understand the fundamental concepts of NMR. It is assumed that the reader already understands the quantum numbers associated with electrons.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_Background_Physics_and_MathematicsA=A+1e+1+A0e0+A−1e−1=A+1e++1+A0e+0+A−1e+−1 \[A \times B=\begin{bmatrix} a_{11}b_{11} & a_{11}b_{12} & a_{12}b_{11}& a_{12}b_{12}\\ a_{11}b_{21} & a_{11}b_{22} & a_...A=A+1e+1+A0e0+A−1e−1=A+1e++1+A0e+0+A−1e+−1 A×B=[a11b11a11b12a12b11a12b12a11b21a11b22a12b21a12b22a21b11a21b12a22b11a22b12a21b21a21b22a22b21a22b22]
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR%3A_Experimental/Solid_State_NMR_Experimental_SetupThis section is devoted to giving a practical guide for solid state NMR. Please follow all safety guidelines at your University. All experiments are performed on a 500MHz magnet using a Bruker AQS spe...This section is devoted to giving a practical guide for solid state NMR. Please follow all safety guidelines at your University. All experiments are performed on a 500MHz magnet using a Bruker AQS spectrometer running TopSpin 2.1. Please note that your spectrometer may be different and/or run different software in which some/all of the commands listed below will be different.
- https://chem.libretexts.org/Courses/University_of_California_Davis/Chem_205%3A_Symmetry_Spectroscopy_and_Structure/05%3A_Magnetic_Resonance_Spectroscopies/5.02%3A_Nuclear_Magnetic_Resonance_(NMR)_-_Turning_on_the_FieldThe absence of external fields, there is no preferred orientation for a magnetic moment. That is, the different m values of the orientation of the spin are degenerate. However, since a nucleus is a...The absence of external fields, there is no preferred orientation for a magnetic moment. That is, the different m values of the orientation of the spin are degenerate. However, since a nucleus is a charged particle in motion, it will develop a magnetic field. Randomly oriented nuclear spins are aligned when a magnetic field applied on it. Hence, in the presence of a magnetic field, the energy of a magnetic moment depends on its orientation relative to the applied field lines.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_Theory/NMR_Interactions/Chemical_Shift_(Shielding)As electrons orbit the nucleus, the slightly alter the magnetic field that the nucleus experineces, which slightly changes the difference between the energy levels which gives the resulting spectra. T...As electrons orbit the nucleus, the slightly alter the magnetic field that the nucleus experineces, which slightly changes the difference between the energy levels which gives the resulting spectra. The average timescale of rotation for a liquid is on the order of picoseconds which is about 1 trillion times larger than the CSA . For solids the case is more interesting as increasing the temperature can give rise to molecular motion.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_Theory/NMR_Interactionswhere H Zeeman is the Zeeman interaction, H J is the J coupling, H CS is the chemical shift coupling, H DD is the dipolar coupling, and H Q is the quadrupolar coupling. The Zeeman interaction is the l...where H Zeeman is the Zeeman interaction, H J is the J coupling, H CS is the chemical shift coupling, H DD is the dipolar coupling, and H Q is the quadrupolar coupling. The Zeeman interaction is the largest, followed by the quadrupolar interactions which are on the order of MHz. The chemical shift and the dipolar coupling are on the order of kHz while the scalar coupling is the smallest which is only tens of Hz.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR%3A_Experimental/Diffusion_Ordered_Spectroscopy_(DOSY)Diffusion Ordered SpectroscopY (DOSY) utilizes magnetic field gradients to investigate diffusion processes occurring in solid and liquid samples.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_Theory/Quantum_Mechanic_Treatment\[ \rho(t)=R(t) \sigma(t) R^{\dagger}(t)=\frac{1}{2} \begin{bmatrix} e^{\frac{i \omega_0 t}{2}} & 0 \\ 0 &e^{\frac{-i \omega_0 t}{2}} \end{bmatrix} \begin{bmatrix} \cos \omega_1 t & -i\sin \omega_1 t\...ρ(t)=R(t)σ(t)R†(t)=12[eiω0t200e−iω0t2][cosω1t−isinω1t−isinω1tcosω1t][e−iω0t200eiω0t2]=[cosω1t−isinω1teiω0t−isinω1te−iω0tcosω0t]
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/NMR_-_Theory/Rotations_and_Irreducible_Tensor_OperatorsIrreducible Tensor Operators are extremely valuable to help reduce complex mathematical problems commonly found in NMR. This page will be devoted to deriving the tensors and showing how to use the ten...Irreducible Tensor Operators are extremely valuable to help reduce complex mathematical problems commonly found in NMR. This page will be devoted to deriving the tensors and showing how to use the tensors in calculations.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Magnetic_Resonance_Spectroscopies/Nuclear_Magnetic_Resonance/Nuclear_Magnetic_Resonance_IINuclear Magnetic Resonance (NMR) is a nuclei (Nuclear) specific spectroscopy that has far reaching applications throughout the physical sciences and industry. NMR uses a large magnet (Magnetic) to pro...Nuclear Magnetic Resonance (NMR) is a nuclei (Nuclear) specific spectroscopy that has far reaching applications throughout the physical sciences and industry. NMR uses a large magnet (Magnetic) to probe the intrinsic spin properties of atomic nuclei. Like all spectroscopies, NMR uses a component of electromagnetic radiation (radio frequency waves) to promote transitions between nuclear energy levels (Resonance). Most chemists use NMR for structure determination of small molecules.
